Urge to fight: one’s content to be beaten eventually? (3-3)

I believe the answer is:

egg-box

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'one's content to be beaten eventually?' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'urge to fight' is the wordplay.
'urge' becomes 'egg' (as in egging someone on).
'to fight' becomes 'box' (boxing is a kind of fighting).
'egg'+'box'='EGG-BOX'

Can you help me to learn more?

I've seen this clue in The Times.

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